Wipe for killing spores

ABSTRACT

This invention relates to a wipe for killing spores comprising an absorbent sheet holding an aqueous composition and a sealed package containing the absorbent sheet, wherein the aqueous composition comprises water, an antimicrobial agent and a peroxide. The invention also relates to a process for killing spores using the above-indicated wipe.

This application is a continuation-in-part of U.S. application Ser. No.14/262,840, filed Apr. 28, 2014. This application is also acontinuation-in-part of U.S. application Ser. No. 14/525,497, filed Oct.28, 2014. This application is also a continuation-in-part of U.S.application Ser. No. 14/538,011, filed Nov. 11, 2014. This applicationis also a continuation-in-part of U.S. application Ser. No. 14/537,958,filed Nov. 11, 2014. These prior applications are incorporated herein byreference.

TECHNICAL FIELD

This invention relates to wipes for killing spores, and moreparticularly, to a wipe comprising an absorbent sheet holding an aqueouscomposition, and a sealed package containing the absorbent sheet,wherein the aqueous composition contains an antimicrobial agent (e.g.,peracetic acid) and a peroxide (e.g., hydrogen peroxide).

BACKGROUND

Spores are a highly resistant, dormant cell type formed by some types ofbacteria. Endospores (or simply spores) form within the vegetativemother cell in response to adverse changes in the environment, mostcommonly nutrient depletion. The mother cell undergoes an asymmetricalcell division, where it replicates its genetic material, which is thensurrounded by multiple concentric and spore specific layers. The mothercell then disintegrates, releasing the mature dormant spore whichrequires neither nutrients, water nor air for survival and is protectedagainst a variety of trauma, including extremes of temperature,radiation, and chemical assault. Spore forming bacteria cause a numberof serious diseases in humans, including botulism, gas gangrene,tetanus, and acute food poisoning. Anthrax results from infection by theaerobic spore form Bacillus anthracis.

SUMMARY

Spores are difficult to kill and a problem in the art of sterilizationrelates to providing effective wipes for killing spores. This inventionprovides a solution to this problem. This invention relates to a wipefor killing spores comprising an absorbent sheet holding an aqueouscomposition, and a sealed package containing the absorbent sheet. Theaqueous composition may comprise water, an antimicrobial agent (e.g.,peracetic acid) and a peroxide (e.g., hydrogen peroxide). Theconcentration of the peroxide may be in the range from about 0.01 toabout 14% by weight, or from about 0.1 to about 6.5% by weight. Theconcentration of the antimicrobial agent is in the range from about0.001 to about 5% by weight, or from about 0.001 to about 0.075% byweight. The weight ratio of the antimicrobial agent to the peroxide maybe in the range from about 0.001 to about 0.5, or from about 0.003 toabout 0.4, or from about 0.006 to about 0.3, or from about 0.008 toabout 0.2, or from about 0.01 to about 0.1. In an embodiment, theaqueous composition may comprise water, peracetic acid and hydrogenperoxide, the concentration of peracetic acid in the water may be in therange from about 0.005 to about 0.075% by weight; the concentration ofthe hydrogen peroxide in the water may be in the range from about 0.1 toabout 6.5% by weight; and the weight ratio of peracetic acid to hydrogenperoxide may be in the range from about 0.001 to about 0.5.

The above-indicated wipe may be used in a process for killing sporespositioned on a substrate. The process may comprise wiping the sporesfrom the substrate using the absorbent sheet holding the aqueouscomposition and contacting the spores with the aqueous composition heldby the absorbent sheet; and maintaining the aqueous composition incontact with the spores for an effective period of time to effect atleast a 4 log reduction, or at least a 5 log reduction, or at least a 6log reduction in the number of spores capable of returning to vegetativegrowth. The effective period of time may be in the range from about 30seconds to about 20 minutes, or from about 30 seconds to about 10minutes.

BRIEF DESCRIPTION OF THE DRAWINGS

In the annexed drawings, like parts and features have like designations.

FIG. 1 is a schematic illustration of a spore that can be killed inaccordance with the invention.

FIG. 2 is a front elevational view of the inventive wipe.

FIG. 3 is a rear elevational view of the inventive wipe.

FIG. 4 is a section view in the direction of arrow 4-4 in FIG. 2.

DETAILED DESCRIPTION

All ranges and ratio limits disclosed in the specification and claimsmay be combined in any manner. It is to be understood that unlessspecifically stated otherwise, references to “a,” “an,” and/or “the” mayinclude one or more than one, and that reference to an item in thesingular may also include the item in the plural.

The phrase “and/or” should be understood to mean “either or both” of theelements so conjoined, i.e., elements that are conjunctively present insome cases and disjunctively present in other cases. Other elements mayoptionally be present other than the elements specifically identified bythe “and/or” clause, whether related or unrelated to those elementsspecifically identified unless clearly indicated to the contrary. Thus,as a non-limiting example, a reference to “A and/or B,” when used inconjunction with open-ended language such as “comprising” can refer, inone embodiment, to A without B (optionally including elements other thanB); in another embodiment, to B without A (optionally including elementsother than A); in yet another embodiment, to both A and B (optionallyincluding other elements); etc.

The word “or” should be understood to have the same meaning as “and/or”as defined above. For example, when separating items in a list, “or” or“and/or” shall be interpreted as being inclusive, i.e., the inclusion ofat least one, but also including more than one, of a number or list ofelements, and, optionally, additional unlisted items. Only terms clearlyindicated to the contrary, such as “only one of” or “exactly one of,”may refer to the inclusion of exactly one element of a number or list ofelements. In general, the term “or” as used herein shall only beinterpreted as indicating exclusive alternatives (i.e. “one or the otherbut not both”) when preceded by terms of exclusivity, such as “either,”“one of,” “only one of,” or “exactly one of.”

The phrase “at least one,” in reference to a list of one or moreelements, should be understood to mean at least one element selectedfrom any one or more of the elements in the list of elements, but notnecessarily including at least one of each and every elementspecifically listed within the list of elements and not excluding anycombinations of elements in the list of elements. This definition alsoallows that elements may optionally be present other than the elementsspecifically identified within the list of elements to which the phrase“at least one” refers, whether related or unrelated to those elementsspecifically identified. Thus, as a non-limiting example, “at least oneof A and B” (or, equivalently, “at least one of A or B,” or,equivalently “at least one of A and/or B”) can refer, in one embodiment,to at least one, optionally including more than one, A, with no Bpresent (and optionally including elements other than B); in anotherembodiment, to at least one, optionally including more than one, B, withno A present (and optionally including elements other than A); in yetanother embodiment, to at least one, optionally including more than one,A, and at least one, optionally including more than one, B (andoptionally including other elements); etc.

The transitional words or phrases, such as “comprising,” “including,”“carrying,” “having,” “containing,” “involving,” “holding,” and thelike, are to be understood to be open-ended, i.e., to mean including butnot limited to. The term “killing” (or “kill”) spores refers torendering the spores incapable of returning to vegetative growth. In anembodiment, the term killing spores refers to rendering the sporesincapable of reproduction, metabolism and/or growth.

The term “log reduction” is a mathematical term to show the number oflive spores killed by contacting the spores with the aqueous compositionof the invention. A “4 log reduction” means that the number of livespores is 10,000 times smaller. A “5 log reduction” means that thenumber of live spores is 100,000 times smaller. A “6 log reduction”means that the number of live spores is 1,000,000 times smaller.

The term “antimicrobial agent” refers to a substance that killsmicroorganisms or inhibits their growth.

The term “disinfectant” refers to a substance that is applied tonon-living objects to kill or inhibit the growth of microorganisms thatare on the objects.

The term “antibiotic” refers to a substance that kills or inhibits thegrowth of microorganisms within the body.

The term “antiseptic” refers to a substance that kills or inhibits thegrowth of microorganisms on living tissue.

The term “biocide” refers to a substance that kills or inhibits thegrowth of living organisms. The biocide can be a pesticide. The biocidecan be a fungicide, herbicide, insecticide, algaecide, molluscicide,miticide or rodenticide.

The term “sanitizer” refers to a substance that cleans and disinfects.

The term “biodegradable” refers to a material which decomposes uponexposure to air.

The inventive wipe may be described with reference to FIGS. 2-4.Referring to FIGS. 2-4, wipe 10 comprises absorbent sheet 12 holding theaqueous composition for killing spores. The absorbent sheet 12 with theaqueous composition is contained within sealed package 14. The sealedpackage 14 has a rectangular shape and is made from non-porous sheets 16and 18. The non-porous sheets 16 and 18 may be hermetically sealedtogether along their peripheral edges 20 to form an inner cavity 22 forcontaining the absorbent sheet 12 and the aqueous composition. Theabsorbent sheet 12 holding the aqueous composition may be referred to asa saturated absorbent sheet. The sealed package 14 includes tear line 24and notch 26 which facilitates opening the package 14 along tear line24. The saturated absorbent sheet 12 may be removed from the sealedpackage 14 by tearing the sealed package 14 along tear line 24, and thenpulling the saturated absorbent sheet 12 out of the torn package.

The absorbent sheet 12 holding the aqueous composition may be referredto as a saturated absorbent sheet. The absorbent sheet may be referredto as a towelette. The absorbent sheet may comprise a wiping padsuitable for wiping a substrate. The absorbent sheet may be made of amaterial that resists disintegration while in use to effect a suitablewiping of a substrate. The absorbent sheet may be biodegradable. Theabsorbent sheet may comprise a woven material, a non-woven material, ora combination thereof. The absorbent sheet may comprise natural fibers,synthetic fibers, or a combination thereof. The absorbent sheet maycomprise paper, cotton, jute, rayon, polyester, acrylonitrile, nylon, ora combination thereof. The absorbent sheet may comprise a spongematerial, polyurethane foam, or a combination thereof. The absorbentsheet may have a surface area in the range from about 5 to about 2000cm², or about 10 to about 1500 cm², or about 20 to about 1000 cm², orabout 50 to about 750 cm², or about 75 to about 500 cm², or about 100 toabout 250 cm². The absorbent sheet may have a thickness that issufficient to absorb and retain the aqueous composition. The absorbentsheet may have a thickness in the range from about 0.01 to about 0.5 cm,or about 0.02 to about 0.4 cm, or about 0.05 to about 0.2 cm. Theabsorbent sheet may be folded to allow for storage in the sealed package14.

The sealed package 14 may be square or rectangular in shape. The sealedpackage may have an air and liquid impermeable construction. The sealedpackage may have a light impermeable construction. The sealed packagemay be made of aluminum foil, plastic sheet, coated paper, or acombination thereof. The sealed package may be made of two non-poroussheets with common peripheral edges sealed together. The sealed packagemay include tear line 24 and notch 26 to facilitate tearing of thesealed package along the tear line. The sealed package may havesufficient dimensions to allow for receiving the absorbent sheet.

The sterilization of spores is often taken as referring to a process forachieving a total absence of living spores. Processes that are lessrigorous than sterilization may include, for example, disinfection,sanitization, decontamination, cleaning, and the like. The wipe providedfor herein may be used to achieve at least a 4 log reduction, or atleast a 5 log reduction, or at least a 6 log reduction in the number ofspores capable of returning to vegetative growth, or in an embodiment,capable of reproduction, metabolism and/or growth. When at least a 6 logreduction is achieved, the result may be referred to as a sterilization.When a 4 log reduction or a 5 log reduction is achieved, the result maybe considered to be less rigorous than a sterilization, but neverthelessuseful for various disinfection, sanitization, decontamination and/orcleaning applications.

Spores typically comprise multiple concentric layers surrounding acentral core. This is illustrated in FIG. 1 wherein a bacterial spore isshown which has a central core, inner membrane, germ cell wall, cortex,outer membrane, spore coat and occasionally an exosporium. Oxidizingagents for years have been thought to attack DNA, RNA, protein and mostorganic matter equally. However, while not wishing to be bound bytheory, with the present invention it is believed that the mechanismthat is provided involves the peroxide (e.g., hydrogen peroxide) firstpiercing holes in multiple layers surrounding the central core of thespores, and then the antimicrobial agent advancing through the piercedholes and attacking the central core to kill the spores. This mechanismis believed to occur when using aqueous compositions with relatively lowconcentrations of the peroxide (e.g., in the range from about 0.01 toabout 14% by weight, or from about 0.1 to about 6.5% by weight). Thismay be particularly so when relatively low concentrations of theantimicrobial agent (e.g., in the range from about 0.001 to about 5% byweight, or from about 0.005 to about 0.075% by weight) are used. In anembodiment, this mechanism is believed to occur when relatively lowconcentrations of the antimicrobial agent and peroxide are used, asindicated above, and the antimicrobial agent to peroxide weight ratio isrelatively low (e.g., in the range from about 0.001 to about 0.5, orabout 0.01 to about 0.1). As such, the ratio of antimicrobial agent toperoxide may be considered important with respect to biocidalpotentials.

The water may comprise tap water, deionized water, distilled water,water purified by osmosis, or a mixture of two or more thereof.

The peroxide may comprise any compound containing an oxygen-oxygensingle bond, or a peroxide group or peroxide ion. Examples includehydrogen peroxide; organic peroxides (e.g., benzoyl peroxide, acetylacetone peroxide, acetyl benzoyl peroxide, diacetyl peroxide, methylethyl ketone peroxide, methyl isobutyl ketone peroxide, acetoneperoxide, or a mixture of two or more thereof); peroxy acids (e.g.,peroxy carboxylic acid); organic hydroperoxides (e.g., t-butylhydroperoxide, ethylhydroperoxide, or cumene hydroperoxide); inorganicperoxides such as peroxide salts (e.g., alkali metal or alkaline earthmetal peroxides); acid peroxides (e.g., peroxymonosulfuric acid orperoxydisulfuric acid); and mixtures of two or more thereof.

The hydrogen peroxide may be derived from any source of hydrogenperoxide. Hydrogen peroxide is typically available as a solution inwater. Hydrogen peroxide concentrations of about 3 to about 8% by weightmay be used. Commercial grades of about 30% to about 40% by weight, orabout 35% by weight, hydrogen peroxide may be used. Commercial grades ofabout 70 to about 98% by weight hydrogen peroxide may be used. Thehigher concentrations would be diluted to provide the desiredconcentrations of hydrogen peroxide that are indicated above.

The concentration of the peroxide in the water may be in the range fromabout 0.01 to about 14% by weight, or from about 0.01 to about 12% byweight, or from about 0.01 to about 10% by weight, or from about 0.01 toabout 8% by weight, or from about 0.01 to about 7% by weight, or fromabout 0.05 to about 7% by weight, or from about 0.1 to about 7% byweight, or from about 0.1 to about 6.5% by weight.

The antimicrobial agent may comprise a disinfectant, antibiotic,antiseptic, biocide and/or sanitizer. The antimicrobial agent maycomprise peracetic acid. The antimicrobial agent may comprise analcohol, chlorine, a chlorine compound, an aldehyde, an oxidizing agent,iodine, ozone, a phenolic, a quaternary ammonium compound, or a mixtureof two or more thereof. The antimicrobial agent may compriseformaldehyde, ortho-phthalaldehyde, glutaraldehyde, silver dihydrogencitrate, polyaminopropyl biguanide, sodium bicarbonate, lactic acid,chlorine bleach, or a mixture of two or more thereof. The antimicrobialagent may comprise methanol, ethanol, n-propanol, 1-propanol,2-propanol, isopropanol, or a mixture of two or more thereof. Theantimicrobial agent may comprise a hypochlorite, chlorine dioxide, adichloroisocyanurate, a monochloroisocyanurate, a halogenated hydantoin,or a mixture of two or more thereof. The antimicrobial agent maycomprise sodium hypochlorite, calcium hypochlorite, sodiumdichloroisocyanurate, sodium chlorite,N-chloro-4-methylbenzenesulfonamide sodium salt, 2,4-dichorobenzylalcohol, or a mixture of two or more thereof. The antimicrobial agentmay comprise performic acid, potassium permanganate, potassiumperoxymonosulfate, or a mixture of two or more thereof. Theantimicrobial agent may comprise phenol, o-phenylphenol, chloroxylenol,hexachlorophene, thymol, amylmetacresol, or a mixture of two or morethereof. The antimicrobial agent may comprise benzalkonuim chloride,cetyltrimethyl ammonium bromide, cetylpyridinium chloride, benzethoniumchloride, boric acid, Brilliant green, chlorhexidine gluconate, tinctureof iodine, providone-iodine, mercurochrome, manuka honey, octenidinedihydrochloride, polyhexamethylene biguamide, balsam of Peru, or amixture of two or more thereof. Many of these antimicrobial agents maynot be effective in the killing of spores on their own, but whencombined with hydrogen peroxide at the concentration levels indicatedabove many of these antimicrobial agents are useful for killing spores.

The concentration of the antimicrobial agent in the aqueous compositionmay be in the range from about 0.001 to about 5% by weight, or fromabout 0.001 to about 4%, or from about 0.001 to about 3% by weight, orfrom about 0.001 to about 2% by weight, or from about 0.001 to about1.5% by weight, or from about 0.001 to about 1% by weight, or from about0.001 to about 0.8% by weight, or from about 0.001 to about 0.5% byweight, or from about 0.001 to about 0.2% by weight, or from about 0.001to about 0.18% by weight, or from about 0.001 to about 0.16% by weight,or from about 0.001 to about 0.14% by weight, or from about 0.001 toabout 0.12% by weight, or from about 0.001 to about 0.1% by weight, orfrom about 0.001 to about 0.08% by weight, or from about 0.001 to about0.075% by weight, or from about 0.001 to about 0.07% by weight, or fromabout 0.001 to about 0.06% by weight, or from about 0.001 to about 0.05%by weight, or from about 0.001 to about 0.04% by weight. Theconcentration of the antimicrobial agent may be in the range from about0.005 to about 0.5% by weight, or from about 0.005 to about 0.4% byweight, or from about 0.005 to about 0.3% by weight, or from about 0.005to about 0.2% by weight, or from about 0.005 to about 0.18% by weight,or from about 0.005 to about 0.16% by weight, or from about 0.005 toabout 0.12% by weight, or from about 0.005 to about 0.1% by weight, orfrom about 0.005 to about 0.08% by weight, or from about 0.005 to about0.075% by weight, or from about 0.005 to about 0.07% by weight, or fromabout 0.005 to about 0.06% by weight, or from about 0.005 to about 0.05%by weight, or from about 0.005 to about 0.04% by weight.

The weight ratio of the antimicrobial agent to peroxide may be in therange from about 0.001 to about 0.5, or from about 0.003 to about 0.4,or from about 0.006 to about 0.3, or from about 0.008 to about 0.2, orfrom about 0.01 to about 0.1.

The aqueous composition may further comprise acetic acid, sulfuric acid,or a mixture thereof. The concentration of acetic acid may range up toabout 60% by weight, or from about 0.001 to about 60% by weight, or fromabout 0.001 to about 30% by weight, or from about 0.001 to about 10% byweight, or from about 0.001 to about 5% by weight, or from about 0.001to about 2% by weight. The concentration of sulfuric acid may range upto 3% by weight, or from about 0.001 to about 2% by weight. Theconcentration of each of these may be in the range up to about 1% byweight, or from about 0.001 to about 1% by weight, or from about 0.001to about 0.5% by weight, or from about 0.001 to about 0.3% by weight.

The aqueous composition may further comprise one or more surfactants toprovide the aqueous composition with surface active properties, one ormore buffers to provide buffering capability (pH modulation), one ormore corrosion inhibitors to provide corrosion inhibiting properties,and/or one or more chelators to provide chelation capacity (watersoftening).

The surfactant may comprise any compound that lowers surface tension orprovides greater wettability. The surfactant may comprise one or moredetergent, wetting agents, emulsifiers, foaming agents and/ordispersants. The surfactant may comprise one or more organic compoundsthat contain both hydrophobic groups and hydrophilic groups. Thesurfactant may comprise both a water insoluble component and a watersoluble component. The surfactant may comprise one or more anionic,cationic, zwitterionic and/or nonionic compounds. The surfactant maycomprise one or more alkanolamines, alkylarylsulfonates, amine oxides,poly(oxyalkylene)s, block copolymers comprising alkylene oxide repeatunits, carboxylated alcohol ethoxylates, ethoxylated alcohols, alkylphenols, ethoxylated alkyl phenols, ethoxylated amines, ethoxylatedamides, oxiranes, ethoxylated fatty acids, ethoxylated fatty esters,ethoxylated oils, fatty esters, fatty acid amides, glycerol esters,glycol esters, sorbitan, sorbitan esters, imidazolines, lecithin,lignin, glycerides (e.g., mono-, di- and/or triglyceride), olefinsulfonates, phosphate esters, ethoxylated and/or propoxylated fattyacids and/or alcohols, sucrose esters, sulfates and/or alcohols and/orethoxylated alcohols of fatty esters, sulfonates of dodecyl and/ortridecyl benzenes, sulfosuccinates, dodecyl and/or tridecyl benzenesulfonic acids, mixtures of two or more thereof, and the like. Thesurfactant may comprise ethanolamine, triethanolamine,octyldimethylamine oxide, nonylphenoxy poly(ethyleneoxy)ethanol,polyalkylene glycol, or a mixture of two or more thereof.

The concentration of the surfactant in the aqueous composition may be inthe range up to about 10% by weight, or from about 0.5 to about 10% byweight, or from about 0.5 to about 6% by weight, or from about 1 toabout 4% by weight.

The buffer may comprise an alkali metal phosphate, an alkali metalcarbonate, or a mixture thereof. The alkali metal may comprise sodium orpotassium. The buffer may comprise one or more of monosodium phosphate,disodium phosphate, trisodium phosphate, monopotassium phosphate,dipotassium phosphate, tripotassium phosphate, sodium carbonate, or amixture of two or more thereof. Disodium phosphate may be used. Theconcentration of the buffer in the aqueous composition may be in therange up to about 50% by weight, or from about 1% by weight to about 50%by weight, or from about 1% by weight to about 40% by weight, or fromabout 5% by weight to about 40% by weight, or from about 5% by weight toabout 35% by weight.

The corrosion inhibitor may comprise benzotriazole, a sodium salt ofbenzotriazole, tolyltriazole, a sodium salt of tolyltriazole, or amixture of two or more thereof. Sodium benzotriazole may be used. Acommercially available sodium benzotriazole that may be used isavailable under the trade designation Cobratec 40S which is believed tobe a 40% by weight aqueous solution of sodium benzotriazole. Theconcentration of the corrosion inhibitor in the aqueous composition maybe in the range up to about 10% by weight, or from about 0.01% by weightto about 10% by weight, or from about 0.01% by weight to about 5% byweight.

The chelator may comprise ethylenediaminetetraacetic acid,hydroxyethylidenediphosphonic acid, a sodium salt of either of theseacids, or a mixture of two or more thereof. A sodium salt ofethylenediaminetetraacetic acid that may be ethylenediaminetetraaceticacid, tetrasodium salt, tetrahydrate. A commercially availableethylenediaminetetraacetic acid, tetrasodium salt, tetrahydrate that maybe used may be available from Akzo Nobel under the trade designationDissolvine 220-S. Dissolvine 220-S is identified by Akzo Nobel as beinga chelating agent containing 83-85% by weight ethylenediaminetetraaceticacid, tetrasodium salt, tetrahydrate. The concentration of the chelatorin the aqueous composition may be in the range up to about 50% byweight, or from about 0.01% by weight to about 50% by weight, or fromabout 0.1% by weight to about 30% by weight.

The aqueous composition may further comprise one or more fragrances,dyes, mixtures thereof, and the like.

The inventive process may comprise killing spores positioned on asubstrate. This process may comprise wiping the spores from thesubstrate using the absorbent sheet holding the aqueous composition. Theaqueous composition may contact the spores and kill them. The aqueouscomposition may remain in contact with the spores for an effectiveperiod of time to effect a desired level of reduction (e.g., at least a4 log reduction, or at least a 5 log reduction, or at least a 6 logreduction) in the number of spores capable of returning to vegetativegrowth, or in an embodiment, capable of reproduction, metabolism and/orgrowth. The aqueous composition may remain in contact with the sporesfor about 30 seconds to about 20 minutes, or about 30 seconds to about10 minutes.

The substrate may be made of any material including brass, copper,aluminum, stainless steel, carbon steel, rubber, plastic, glass, wood,painted surface, or a combination of two or more thereof. The substratemay comprise a table top, counter top, floor, wall, ceiling, window,door, door handle, sink, faucet, toilet, toilet seat, and the like. Thesubstrate may comprise a medical, dental, pharmaceutical, veterinary ormortuary device. The substrate may comprise human skin.

The temperature of the aqueous composition when contacting the sporesmay be in the range from about 1° C. to about 40° C., or from about 5°C. to about 35° C., or from about 10° C. to about 30° C., or from about15° C. to about 30° C., or from about 20° C. to about 26° C., or fromabout 21° C. to about 25° C., or from about 22° C. to about 24° C., orabout 22° C., or about 23° C. The temperature may be room temperature.

The spores that may be treated (i.e., killed) include bacterial spores.The spores may comprise bacteria of the Bacillus or Clostridia genera.The spores may comprise Geobacillus stearothermophilus, Bacillusatrophaeus, Bacillus subtilis, Bacillus pumilus, Bacillus coagulans,Clostridium sporogenes, Bacillus subtilis globigii, Bacillus cereus,Bacillus circulans, Bacillus anthracis, or a mixture of two or morethereof. The spores may comprise one or more Bacillus subtilis strainsand/or wild type Bacillus subtilis spores.

EXAMPLES

The efficacy of the inventive process is assessed using a time killsuspension test method and spores of Bacillus subtilis.

Peracetic acid (PAA) and hydrogen peroxide (H₂O₂) are prepared asconcentrated stocks (3× concentrate). Each test contains 100 μl of thePAA concentrate and 100 μl of the H₂O₂ concentrate. Controls containingonly PAA or H₂O₂ are also prepared. These contain 100 μl of either thePAA concentrate or H₂O₂ concentrate and 100 μl of de-ionized water. Toeach test, 100 μl of spores are added while starting the timerconcurrently. The samples are mixed thoroughly. The temperature of thesamples is room temperature. At the appropriate contact times, 10 μl ofthe appropriate test sample are placed into 90 μl of the appropriateneutralizing solution, mixed thoroughly and incubated for at least 10minutes. Ten fold serial dilutions are prepared through 10⁻⁶ and platedusing the drop counting method. The plates are then incubatedaerobically at 37° C. for 1-2 days. Following incubation, colony formingunits (CFU) are counted using standard plate count techniques andconverted to log10 values for analysis.

The results are indicated in the tables below.

TABLE 1 Time (min) to achieve 4 log reduction for various PAA/H₂O₂combinations (calculated from curves fitted to time/kill data) PAAconcentration (% by weight) 0.00 0.005 0.01 0.02 0.04 0.08 0.16 ntration6.40 48.64 15.68 7.2 7.36 3.67 2.14 1.36 (%) 3.20 97.28 15.68 13.12 8.243.92 2.28 1.68 (%) by 1.60 168.96 28.16 24.32 14.08 4.64 3.52 1.82 0.80343.04 33.7 32.96 19.36 7.6 3.96 1.9 0.40 639.34 92.16 69.12 43.52 14.086.4 2.08 0.20 1213.99 286.72 209.12 92.16 32 11.92 2.22 0.10 2305.13 — —337.92 54.4 19.36 3.28 0.00 — 711625 67744.68 6449.101 613.9362 70.404.64

TABLE 2 PAA kill time divided by PAA/H₂O₂ kill time from values in table1 (i.e. Potentiation of PAA activity in the presence of H₂O₂) PAAconcentration (% by weight) 0.00 0.005 0.01 0.02 0.04 0.08 0.16 H₂O₂6.40 — 45384.25 9408.98 876.24 167.29 32.90 3.41 concen- 3.20 — 45384.255163.47 782.66 156.62 30.88 2.76 tration 1.60 — 25270.77 2785.55 458.03132.31 20.00 2.55 (% by 0.80 — 21116.47 2055.36 333.11 80.78 17.78 2.44weight) 0.40 — 7721.63 980.10 148.19 43.60 11.00 2.23 0.20 — 2481.95323.95 69.98 19.19 5.91 2.09 0.10 — — — 19.08 11.29 3.64 1.41

TABLE 3 H₂O₂ kill time divided by PAA/H₂O₂ kill time from values intable 1 (i.e. Potentiation of H₂O₂ activity in the presence of PAA) PAAconcentration (% by weight) 0.00 0.005 0.01 0.02 0.04 0.08 0.16 H₂O₂6.40 — 3.10 6.76 6.61 13.25 22.73 35.76 concen- 3.20 — 6.20 7.41 11.8124.82 42.67 57.90 tration 1.60 — 6.00 6.95 12.00 36.41 48.00 92.84 (% by0.80 — 10.18 10.41 17.72 45.14 86.63 180.55 weight) 0.40 — 6.94 9.2514.69 45.41 99.90 307.38 0.20 — 4.23 5.81 13.17 37.94 101.84 546.84 0.10— — — 6.82 42.37 119.07 702.78

The values shown in Table 1 represent the time taken (minutes) toachieve a 4 log reduction in spore count in the presence of either PAAor H₂O₂ alone, or in combination with each other. For PAA concentrations0.005, 0.01, 0.02 and 0.04% (in the absence of H₂O₂), the values shownare extrapolated based on the experimental data obtained for PAAconcentrations 0.08, 0.16 and 0.32%. Similarly, for H₂O₂ concentrations0.1, 0.2 and 0.4% (in the absence of PAA), the values shown areextrapolated from experimental data. All other values are generated fromspore kill data.

Table 2 illustrates the potentiation of spore killing by PAA when in thepresence of H₂O₂. At higher PAA concentrations (0.08 and 0.16% PAA)relatively little activity is gained by the addition of even very highconcentrations of H₂O₂. For example, 0.16% PAA is only 3.41 times moreactive in the presence of 6.4% H₂O₂, as compared to the activity of0.16% PAA alone.

However, as the concentration of PAA is reduced, the effect of addingH₂O₂ becomes more dramatic, with PAA spore killing activity beinghundreds, thousands and even tens of thousands of times greater when inthe presence of low concentrations of H₂O₂. For example, 0.02% PAA is333.11 times more active in combination with 0.8% H₂O₂ than when usedalone.

Table 3 illustrates the potentiation of spore killing by H₂O₂ when inthe presence of PAA. The enhancement of the spore killing activity ofH₂O₂ when in the presence of PAA is far less pronounced, with relativeimprovement in the spore killing activity of H₂O₂ in combination withall but the highest concentrations of PAA being no greater than about100 times.

While the invention has been explained in relation to variousembodiments, it is to be understood that modifications thereof maybecome apparent to those skilled in the art upon reading thespecification. Therefore, it is to be understood that the scope of theinvention specified herein is intended to include all modifications thatmay fall within the scope of the appended claims.

1. A wipe for killing spores, comprising: an absorbent sheet holding anaqueous composition for killing spores; and a sealed package containingthe absorbent sheet; wherein the aqueous composition comprises water; anantimicrobial agent; and a peroxide; the concentration of the peroxidein the water being in the range from about 0.01 to about 14% by weight.2. The wipe of claim 1 wherein the absorbent sheet comprises a wipingpad suitable for wiping a substrate.
 3. The wipe of claim 1 wherein theabsorbent sheet is made of a material that resists disintegration whilein use to effect suitable wiping of a substrate.
 4. The wipe of claim 1wherein the absorbent sheet is biodegradable.
 5. The wipe of claim 1wherein the absorbent sheet comprises a woven material, a non-wovenmaterial, or a combination thereof.
 6. The wipe of claim 1 wherein theabsorbent sheet comprises a natural fiber, a synthetic fiber, or acombination thereof.
 7. The wipe of claim 1 wherein the absorbent sheetcomprises paper, cotton, jute, rayon, polyester, acrylonitrile, nylon,or a combination thereof.
 8. The wipe of claim 1 wherein the absorbentsheet comprises a sponge material, polyurethane foam, or a combinationthereof.
 9. The wipe of claim 1 wherein the absorbent sheet has asurface area of about 5 to about 2000 cm².
 10. The wipe of claim 1wherein the absorbent sheet has a thickness that is sufficient to absorband retain the aqueous composition.
 11. The wipe of claim 1 wherein theabsorbent sheet has a thickness in the range from about 0.01 to about0.5 cm.
 12. The wipe of claim 1 wherein the sealed package is square orrectangular in shape.
 13. The wipe of claim 1 wherein the sealed packagehas an air and liquid impermeable construction.
 14. The wipe of claim 1wherein the sealed package has a light impermeable construction.
 15. Thewipe of claim 1 wherein the sealed package is made of aluminum foil,plastic sheet, coated paper, or a combination thereof.
 16. The wipe ofclaim 1 wherein the sealed package is made of two non-porous sheets withcommon peripheral edges sealed together.
 17. The wipe of claim 1 whereinthe sealed package includes a tear line and a notch to facilitatetearing of the sealed package along the tear line.
 18. The wipe of claim1 wherein the concentration of the antimicrobial agent is in the rangefrom about 0.001 to about 5% by weight.
 19. The wipe of claim 1 whereinthe concentration of the antimicrobial agent is in the range from about0.001 to about 0.075% by weight.
 20. The wipe of claim 1 wherein theconcentration of the antimicrobial agent is in the range from about0.005 to about 0.075% by weight.
 21. The wipe of claim 1 wherein theweight ratio of the antimicrobial agent to the peroxide is in the rangefrom about 0.001 to about 0.5.
 22. The wipe of claim 1 wherein the watercomprises tap water, deionized water, distilled water, water purified byosmosis, or a mixture of two or more thereof.
 23. The wipe of claim 1wherein the peroxide is a compound containing an oxygen-oxygen singlebond, a peroxide group and/or a peroxide ion.
 24. The wipe of claim 1wherein the peroxide comprises an organic peroxide, a peroxy acid, anorganic hydroperoxide, an inorganic peroxide, an acid peroxide, or amixture of two or more thereof.
 25. The wipe of claim 1 wherein theperoxide comprises hydrogen peroxide.
 26. The wipe of claim 1 whereinthe antimicrobial agent comprises a disinfectant, antibiotic,antiseptic, biocide and/or sanitizer.
 27. The wipe of claim 1 whereinthe antimicrobial agent comprises peracetic acid.
 28. The wipe of claim1 wherein the antimicrobial agent comprises an alcohol, chlorine, achlorine compound, an aldehyde, an oxidizing agent, iodine, ozone, aphenolic, a quaternary ammonium compound, or a mixture of two or morethereof.
 29. The wipe of claim 1 wherein the antimicrobial agentcomprises formaldehyde, ortho-phthalaldehyde, glutaraldehyde, silverdihydrogen citrate, polyaminopropyl biguanide, sodium bicarbonate,lactic acid, chlorine bleach, or a mixture of two or more thereof. 30.The wipe of claim 1 wherein the antimicrobial agent comprises methanol,ethanol, n-propanol, 1-propanol, 2-propanol, isopropanol, or a mixtureof two or more thereof.
 31. The wipe of claim 1 wherein theantimicrobial agent comprises a hypochlorite, chlorine dioxide, adichloroisocyanurate, a monochloroisocyanurate, a halogenated hydantoin,or a mixture of two or more thereof.
 32. The wipe of claim 1 wherein theantimicrobial agent comprises sodium hypochlorite, calcium hypochlorite,sodium dichloroisocyanurate, sodium chlorite,N-chloro-4-methylbenzenesulfonamide sodium salt, 2,4-dichorobenzylalcohol, or a mixture of two or more thereof.
 33. The wipe of claim 1wherein the antimicrobial agent comprises performic acid, potassiumpermanganate, potassium peroxymonosulfate, or a mixture of two or morethereof.
 34. The wipe of claim 1 wherein the antimicrobial agentcomprises phenol, o-phenylphenol, chloroxylenol, hexachlorophene,thymol, amylmetacresol, or a mixture of two or more thereof.
 35. Thewipe of claim 1 wherein the antimicrobial agent comprises benzalkonuimchloride, cetyltrimethyl ammonium bromide, cetylpyridinium chloride,benzethonium chloride, boric acid, Brilliant green, chlorhexidinegluconate, tincture of iodine, providone-iodine, mercurochrome, manukahoney, octenidine dihydrochloride, polyhexamethylene biguamide, balsamof Peru, or a mixture of two or more thereof.
 36. The wipe of claim 1wherein the aqueous composition further comprises acetic acid, sulfuricacid, or a mixture thereof.
 37. The wipe of claim 36 wherein the aqueouscomposition further comprises a surfactant, a buffer, a corrosioninhibitor, a chelator, or a mixture of two or more thereof.
 38. The wipeof claim 37 wherein the surfactant comprises a detergent, wetting agent,emulsifier, foaming agent and/or dispersant.
 39. The wipe of claim 37wherein the surfactant comprises an organic compound that containshydrophobic groups and hydrophilic groups.
 40. The wipe of claim 37wherein the surfactant comprises an anionic, cationic, zwitterionicand/or nonionic compound.
 41. The wipe of claim 37 wherein thesurfactant comprises: an alkanolamine; alkylarylsulfonate; amine oxide;poly(oxyalkylene); block copolymer comprising alkylene oxide repeatunits; carboxylated alcohol ethoxylate; ethoxylated alcohol; alkylphenol; ethoxylated alkyl phenol; ethoxylated amine; ethoxylated amide;oxirane; ethoxylated fatty acid; ethoxylated fatty ester; ethoxylatedoil; fatty ester; fatty acid amide; glycerol ester; glycol ester;sorbitan; sorbitan ester; imidazoline; lecithin; lignin; glyceride;olefin sulfonate; phosphate ester; ethoxylated fatty acid; propoxylatedfatty acid; ethoxylated fatty alcohol; propoxylated fatty alcohol;sucrose ester; sulfate, alcohol and/or ethoxylated alcohol of a fattyester; sulfonate of dodecyl and/or tridecyl benzene; sulfosuccinate;doecyl and/or tridecyl benzene sulfonic acid; or a mixture of two ormore thereof.
 42. The wipe of claim 37 wherein the surfactant comprisesethanolamine, triethanolamine, octyldimethylamine oxide, nonylphenoxypoly(ethyleneoxy)ethanol, polyalkylene glycol, or a mixture of two ormore thereof.
 43. The wipe of claim 37 wherein the buffer comprises analkali metal phosphate, an alkali metal carbonate, or a mixture thereof.44. The wipe of claim 37 wherein the corrosion inhibitor comprisesbenzotriazole, tolyltriazole, a sodium salt of benzotriazole, a sodiumsalt of tolyltriazole, or a mixture of two or more thereof.
 45. The wipeof claim 37 wherein the chelator comprises ethylenediaminetetraaceticacid, hydroxyethylidenediphosphonic acid, a sodium salt ofethylenediaminetetraacetic acid, a sodium salt ofhydroxyethylidenediphosphonic acid, or a mixture of two or more thereof.46. The wipe of claim 1 wherein the aqueous composition furthercomprises a dye, fragrance, or mixture thereof.
 47. The wipe of claim 1wherein the aqueous composition comprises from about 0.1 to about 6.5%by weight hydrogen peroxide, and from about 0.005 to about 0.16% byweight peracetic acid.
 48. The wipe of claim 1 wherein the aqueouscomposition comprises from about 0.1 to about 6.5% by weight hydrogenperoxide, and from about 0.005 to about 0.075% by weight peracetic acid.49. A wipe for killing spores, comprising: an absorbent sheet holding anaqueous composition for killing spores; and a sealed package containingthe absorbent sheet; wherein the aqueous composition comprises water,peracetic acid and hydrogen peroxide; the concentration of the peraceticacid in the water being in the range from about 0.005 to about 0.075% byweight; the concentration of the hydrogen peroxide in the water being inthe range from about 0.1 to about 6.5% by weight; the weight ratio ofthe peracetic acid to the hydrogen peroxide being in the range fromabout 0.001 to about 0.5.
 50. A process for killing spores positioned ona substrate, comprising: wiping the spores from the substrate using theabsorbent sheet of claim 1 and contacting the spores with the aqueouscomposition held by the absorbent sheet; and maintaining the aqueouscomposition in contact with the spores for an effective period of timeto effect at least a 4 log reduction in the number of spores capable ofreturning to vegetative growth.
 51. The process of claim 50 wherein thesubstrate is made of a material comprising brass, copper, aluminum,stainless steel, carbon steel, rubber, plastic, glass, wood, paintedsurface, or a combination of two or more thereof.
 52. The process ofclaim 50 wherein the substrate comprises a table top, counter top,floor, wall, ceiling, window, door, door handle, sink, faucet, toilet ortoilet seat.
 53. The process of claim 50 wherein the substrate comprisesa medical, dental, pharmaceutical, veterinary or mortuary device. 54.The process of claim 50 wherein the substrate comprises human skin. 55.The process of claim 50 wherein the temperature of the aqueouscomposition is in the range from about 1° C. to about 40° C.
 56. Theprocess of claim 50 wherein the effective period of time is from about30 seconds to about 20 minutes.
 57. The process of claim 50 wherein thespores comprise bacterial spores.
 58. The process of claim 50 whereinthe spores comprise bacteria of the Bacillus or Clostridia genera. 59.The process of claim 50 wherein the spores comprise Geobacillusstearothermophilus, Bacillus atrophaeus, Bacillus subtilis, Bacilluspumilus, Bacillus coagulans, Clostridium sporogenes, Bacillus subtilisglobigii, Bacillus cereus, Bacillus circulans, Bacillus anthracis, or amixture of two or more thereof.
 60. The process of claim 50 wherein thespores comprise one or more Bacillus subtilis strains.
 61. The processof claim 50 wherein the aqueous composition is maintained in contactwith the spores for an effective period of time to effect at least a 5log reduction in the number of spores capable of returning to vegetativegrowth.
 62. The process of claim 50 wherein the aqueous composition ismaintained in contact with the spores for an effective period of time toeffect at least a 6 log reduction in the number of spores capable ofreturning to vegetative growth.